To meet the demand for wireless data traffic having increased since deployment of 4G (4th-Generation) communication systems, efforts have been made to develop an improved 5G (5th-Generation) or pre-5G communication system. Therefore, the 5G or pre-5G communication system is also called a ‘Beyond 4G Network’ or a ‘Post LTE System’.
The 5G communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, so as to accomplish higher data rates. To decrease propagation loss of the radio waves and increase the transmission distance, the beamforming, massive multiple-input multiple-output (MIMO), full dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in 5G communication systems.
In addition, in 5G communication systems, development for system network improvement is under way based on advanced small cells, cloud radio access networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, coordinated multi-points (CoMP), reception-end interference cancellation and the like.
In the 5G system, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) as an advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as an advanced access technology have been developed.
Communication systems are being developed aiming increased throughput. Latency plays a role as a critical variable in increasing throughput. For next-generation communication systems, ultra-realistic services are under discussion, and such ultra-realistic services require very short latency. An example of latency required in an ultra-realistic service is one second for sense of pain, 100 milliseconds for auditory sense, 10 milliseconds for visual sense, and one millisecond for tactile sense. For next-generation communication systems, the data rate is expected to be sharply increased.
Meanwhile, as a transport layer, the transmission control protocol (TCP) is mostly used between a user equipment (UE) and a server providing a service to the UE. However, the TCP, by its nature, has a limitation in reducing latency. For example, assuming that the TCP uses a window scheme for flow control, the UE transmits data corresponding to a predetermined window size and increases the window size to thereby increase the data transmitted. However, when the transmitted data is damaged or has an error, the TCP controls the data rate by reducing the window size in half. Accordingly, the latency of transport layer is increased.
Accordingly, in order to meet the latency required by the next-generation communication system, it is material to reduce the latency of transport layer, and research is required to reduce the latency of transport layer.
Meanwhile, the above-described information is provided only as background information for a better understanding of the present disclosure. No determinations and claims are made as to whether what has been described in this section may be applicable as the prior art related to the present disclosure.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.